Printed Circuit Board Question.
 

So, the Smonelli super-automatic espresso machine took a small dump. Indicated a "Coffee temp sensor error."

Anyway, I downloaded schematics and looked up the part. $39. No prob. Called Nuova Simonelli, and they suggested I take it to a local Italian Food Service Co. for repair.

So, in good faith, I took it over. $85/hr, one hour minimum. That's fine.

So, THREE WEEKS LATER, the tech, who funny enough was named "Luigi", called and said "I think I've narrowed it down to the temperature sensor."

"You mean when you turn on the machine and it says "WARNING: TEMPERATURE SENSOR"? Okay, Luigi. Thanks.

Anyway, I approved the installation of a new sensor, and he said he would button it up that day.

ONE WEEK LATER, They call. "Uhhhhh, well, we can't get the machine to heat, we think it's the main board.

New board is $632.

"Sorry guys", I say. "I'll come get it."






So, I get the machine home and tear into it. Unfortunately, LUIGI connected a few of the single-wire spade connectors onto the main board BACKWARDS. No electrical problem, but a problem that most likely made him replace the relay that he replaced on the board.


So, if Luigi can't even keep the connectors straight, and I have a schematic, I'm going to fix it myself. If I screw the pooch, I can buy and replace the main board, which was what he was going to do anyway.

I replaced the old board correctly into the machine and it heats fine, but the temp relay won't switch off. The new relay soldered into the board by Mario, er, I mean Luigi, had kind of a goober-ed up solder job, so I'm hitting the solder joints again.



My question, should these big fat printed traces on the back of the board (behind the relays) have continuity with each other? i'm talking about the three main big ones. They should have continuity amongst themselves, right?


I'm just trying to avoid the buying a new $6xx main board if at all possible. I'd call and scream at Luigi, but I'm not going to let his worthless ass occupy space in my brain.

TIA!

http://forums.pelicanparts.com/uploa...1261806830.jpg

Pretty sure real coboys don't drink espresso.
Buy a $19.95 Mr. Coffee machine and have a real cup a joe.

Can you post a better pic?

Sorry, Dave, I'm stuck with the phone right now.

My concern is the three big areas right here, the goobered-up solder joints were towards the bottom there.

As I understand it, the points inside each of the three sections should have continuity with each other right?

There's also the (not covered in resin) tracer that goes through that third, upside-down 'L" section.
He kinda goobered that up, but should it matter? since all those points have continuity with each other anyway?

http://forums.pelicanparts.com/uploa...1261808009.jpg

The bigger the blob the better the job :)

It does look like the solder mask was not applied to the copper in that pattern so that when it was flow soldered it would plate that area.
As to why they would do that I have no idea.

Want to post the link to the schematic or a picture?

The schematic doesn't go to component level, it just shows the destinations of the molex and ribbon connectors. :(

The section in question connects "FA1" to the relays, I assume it is the ground pathway for the relays. "FA2 and FA3" are the boiler heaters. When the machine gets to temp, the relays are supposed to click off.

http://forums.pelicanparts.com/uploa...1261809222.jpg

Call the company to ask :-)
ask and ask :-)
they might just give you a new Mario board :-)

Oh!
Maybe luigi is pissed that he didn't get the smash bros game!

Jeremy, clean the resin off with q-tips and rubbing alcohol or contact cleaner. If you have solder wick, clean the joints off and carefully resolder, try not to touch each connection together.

Hey Jer, google the relay p/n and get a schematic of the pin out, that will help us figure this **** show out.. glad to hear it at least heats now

I can't tell from the picture which solder joints are the issue. If the flat copper trace is continous, the solder can touch. If the solder runs across the board to another trace, there is the doo-doo.

Oh, and make sure the new relay isn't fried into the on position, from the connectors being hooked up wrong. I've seen things like that before, and worse...

If you put an ohm meter on the leads from one trace to another, you may be going through the components. Hard to tell what readings you may get. I would desolder the work he did and clean all traces using as little heat and time as possible. Re-insert components and use solder SPARINGLY! I know it's fun to say "bigger the blob..." but that just means you are not heating it correctly/sufficiently and staying on the component too long. As you know, heat is the enemy for components.

If no joy, put on the hat, call the manufacturer and use your coboy voice "Hey Darlin', muh cawfee pot done took a dirt nap me. Whut does a fella gotta do ta git a replacement board?" SmileWavy

I know, sorry bout the pic.

The main question to me is the upside down "L" trace. There's the printed "L" trace, and then there's the solder trace down the middle of it, with no resin. All the contacts inside the trace have continuity with each other, so I don't understand what the whole "additional" solder trace thing is about.

The "brand new relay" he soldered in represents the 8 points on the bottom of that picture, many near that 'solder trace', which he goobered and kind of re-connected with a new line of solder.

Thanks!

Next time buy a 20dollar GE coffee machine like i have. If it breaks, $20.00 and you got a brand new one. :-P

Did he put in a new relay or temp sensor? The relay may be functioning ok, the the temp sensor is stuck on. If that doesn't help, de-solder the relay and put back on with care.

Remember, if we can't fix it, it's broke!

Thanks, Einstein.
:D

Debug it one step at a time.

As I read the above, error messages are out, but the heater does not turn off? You should be able to hear or feel the relay click. If not, the relay is stuck, or not getting the signal to change.

Is this correct? If it was the trace & solder, I would think it would not conduct and would not heat up in the first place.

He installed a new temp sensor, which made the warning go away. I have the old one, and when I stuck it back in I got the error message again. So I'm assuming the 'temp sensor" situation is taken care of.

For some reason, he did install a new relay, which is the "coffee boiler" relay.

I dont know if he decided to do this -after- or -before- he put the circuit board back in wrong.

Regardless, I don't want to throw down $85/hr to have him experiment on it. I can do it for free, and I have modicum of experience with these things, so I think I can do it.


So, there's a new relay, which should switch the element OFF when it gets to temp. I can hear the relay click when turning on the power, so that's where I'm at.

Now I'll take the relay out completely and clean up and reinstall, hopefully with better solder joints.

Thanks

All of the pins within a copper pad should have continuity.

You should also get continuity from one pad to the next depending on the state of the relay.

There may be a diagram on top of the relay showing which pins are which.

N.O. is Normally Open, N.C. is Normally Closed.

You should get continuity (and coil resistance) across the relay coil.

You can actuate the relay by putting voltage on the coil and test the continuity through the relay contacts.

(ALTHOUGH, testing relay functionality with a multimeter is tricky as you may not have enough "minimum load" across the contacts to get a reading. Actuating the relay many times may scrub the contacts clean in this case.)

You should hear/feel a click when the coil is actuated, and the relay changes state.

Hope that helps!

Martin

If it is a multi-layer board, I wouldn't remove it unless you have experience with these kind of repairs.

In fact, that may be the problem, if he replaced the relay and there are traces on the component side of the board that were damaged.

Follow the traces to the relay, and see if they all conduct to the corresponding relay terminals, from the other components.

Try to get a schematic of the board from the manufacturer, and we'll be able to diagnose.

Edit: looking back at the pics, I can see traces through the board that look like they go to the relays. See if they conduct and confirm that they should go to the relay. If they do not conduct, rather than disturb the parts, add a jumper wire. When he removed the relay, he may have disturbed the plated through holes.

Take a picture of the other side. Do you have the original relay? If so, take pics of that. If you have a good looking wife, gf or daughter, this thread could use some upgrading...

It is a multi-layer board, but everything checks out on the front side as far as I can tell. Some of the traces on the front side are VERY small, though. In addition I can't really see which pins of the relay the front side traces go to.

Maybe it's time for a new camera, I know.

"9544" is the new relay, the one next to it is unlabled, except for a date. I suppose if I take out the "new" one, the info for the old one is on the side I can't see.

I did not get my "old" relay back.

http://forums.pelicanparts.com/uploa...1261864505.jpg





Sorry, Red. Maybe this will help. :D

http://forums.pelicanparts.com/uploa...1186950837.jpg

http://forums.pelicanparts.com/uploa...1261865652.jpg

I circled the connections that 'switch' the relay. Check them carefully, and follow them if possible.

Is the one on the right shorting to the hole next to it? And if it is, should it be?

Think the tech that worked on it has a schematic for the board?

Dad,

Yes, the connection you're asking about DOES have continuity with the hole. They are tied together via a trace that is difficult to see under the burnt resin. The hole leads to a front-side trace and off to an IC. Same for the other relay.

Thank you!

http://forums.pelicanparts.com/uploa...1261868188.jpg

Take a look at my notes

Based on this, I don't think there are any issues with the connections in the long L shaped part of the trace.

Are both relays stuck on? If so, then the T-Switch circuit which activates the relays is still crapped out.

I also see that if he switched leads around, he might have fried a relay, or more precisley, fried it on. You would be putting all the juice through one relay which feeds both boilers (twice what it is rated for). The other one will get power as normal. Twice the rated current might fuse the contacts together, making it "stick" in the on position. I've seen it happen. You might consider replacing both relays again.

Before you go ANY further, check to see if there is continuity Between FA1 and FA2, and then Check FA1 to FA3. This is of course with the power not turned on!!!!!!!

If there is continuity between FA1 & FA2 or FA1 & FA3, you have a stuck relay, with burned contacts. The associated relay (FA2 or FA3) will need to be replaced.

If there is no continuity issue, then you need to concentrate on the T-switch circuits.

I'm glad I didn't look at the second picture until after getting the "work" done. :D

Thanks, Red.

Yes, your notes are correct.

More info:

The leads the tech had "backwards" are the leads for FA2 and FA3, the higher current connections to the boiler heat coils. One for the "steam boiler" (FA2), and one for the "coffee boiler") FA3.

Technichally, I don't feel that, if switched, they would present a problem, it's just that the boilers would be heating at improper temps.

However, I agree that maybe I will replace BOTH relays, since it's only a $20 run for the gold, as opposed to my more-expensive alternative.

Thanks!

See my post about checking continuity. If one of the boilers pulls more current than the other, then the relay could be fried as I described.

NO continuity between FA1 and either FA2 or FA3.

The relay I can see is a Potter & Brumfield

RKS-11DX-24

10A 250V AC or 30VDC

SPST? There's only one little switch icon on the side.

There's your problem...

Potter & Brumfield

I mean, who uses Potter & Brumfield anyway?

Italian guys named Luigi, apparently.

If there is no continuity when off, and the boilers turn on when the unit is powered, the relays are not the problem. Look to the circuit activating the relays, the part I've labeled T-Switch connection.

Well, I've reviewed both the electrical wiring diagram and the parts book. The temp probes are the same, so they are not switches, but RTDs, or maybe thermistors. You can adjust the temp settings of these (I looked at the manual!).

At this point, I think Mario or Luigi or who ever worked on the machine, screwed something up in the process of changing a simple temp probe. You may indeed have a dead board, now. You need to talk with him and find out why he changed the relay.

Since you are local, a personal visit would simplify things. PM sent.

This is one of the best threads this year I swear!

Think I'll go fire up my $20.00 Braun and have some Joe now.

Jeremy... Aren't those Jims step dtrs?

That is why I mentioned that you should ask the company about their procedures. I had a feeling that Mario / Luigi bros had dinged your board by not fixing it correctly.

Ask for procedures first, then ask what is proper fixing methods, then mention what you got.
With the advice you'Re getting from red and slo you have enough ammo to bing Mario.

The company might just relent to either a new working board or to a new board for the price of the original repair bill (just the sensor repair).

@ girls ...
lolo, I had to double check if duel wasn't posting :D
IF I only was younger :(

What exactly were you refering to Jeremy ?? Burnt resin has blurred my vision more than once too

I'm always here for you bro! :D

A man after my own heart. ;)

And another one!

update:
 

So, for those watching, thanks for your help.

Since my last post I removed the (recently professionally installed :rolleyes:) relay, which was the power relay for the "coffee boiler" heat-coil.

Keep in mind, right next to it, was the untouched (orig) chinese relay, for the steam boiler. Both relays are SPDT relays.

The new relay, when removed, has something floating around inside it, which leads us to believe it's bad.


So, both relays perform IDENTICAL functions, so since I don't have a schematic that provides component values or anything,

I ASSUME (uh-oh) that both relays should use similar values. That's a fair assumption, right?:confused:


FYI:

The Potter and Brumfield relay that Luigi gave me spec'd as such:

Coil voltage: 24VDC. (important!)
Contact rating: 10A at 250VDC (or10VDC)
On: 8.4V, Off: 1.2V

Fine, but check out the specs of the ORIG RELAY:

Coil voltage: 12VDC (hmmmmmm!)
Contact rating 16A at 240VDC (or24VDC)
On: 8.4V, Off: 1.2V


That leads me to believe that the 24V coil-voltage requirement of Luigi's relay
(BTW that he charged me $15 for, plus the $85/hr)
was not being met, and the coil wasn't even suffiiciently energizing to make the relay
(which has $hit floating around in it anyway)

work.

Am I right? Thank you!

So, I've ordered 2 new relays from digikey that spec out much more similar to the ORIGINAL relay, and those should be here sometime next week.
SmileWavySmileWavySmileWavy